soup up

verb2

1. •
   (informal) To modify the engine of (a motor vehicle) to give a higher performance than the specifications.

   • Imagine souping up a Mini with a Cosworth engine: the car would fly. — 2009
2. •
   (figurative) To embellish with many additions.

   • They are dickering over a tax cut small enough, in a bill "souped" up with gadgets, to escape or override a veto. — 1948